Recently, information technology products such as cellular phones, smart phones, tablet PCs and notebook PCs, in which ultracompact digital cameras are incorporated, are being actively developed.
A camera module, which is incorporated in small-sized electronic products such as smart phones, is manufactured by assembling respective components, which have been separately produced, to constitute the camera module.
In the assembly of the camera module, a lens moving apparatus, which constitutes the camera module, may be provided with a magnet for driving a lens, and the magnet may be coupled to a housing by means of an adhesive or the like.
In order to couple the magnet to the housing, an adhesive is first applied to side and upper surfaces of a magnet mounting seat. In the coursed of such application, it is generally difficult to accurately control the quantity of the adhesive that is applied and to uniformly apply the adhesive to the magnet mounting seat. This is because the viscosity of the adhesive may vary depending on the kind of adhesive, the application temperature and the like.
Accordingly, if the quantity of adhesive that is applied is small or the viscosity of the adhesive is not in the proper range, the adhesive does not uniformly spread, thus causing defective adhesion. In this case, when a drop experiment is performed in order to establish the reliability of the product, defective, products in which the magnet is separated from the housing, may be evident.
Once the magnet is bonded to the housing, there is no solution for accurately determining whether a sufficient amount of adhesive has been uniformly applied. Accordingly, there is a need to additionally inject a sufficient amount of adhesive to the bonding area after the magnet is first attached to the housing so as to increase the force of adhesion between the magnet and the housing.
In the operation of attaching the magnet to the housing, when an excessive amount of adhesive is applied to the magnet mounting seat or when the viscosity of the adhesive decreases and the fluidity of the adhesive thus increases, due to the kind of adhesive, the application temperature or the like, even when an appropriate amount of adhesive is applied, the applied adhesive may flow down from the magnet mounting seat.
The adhesive, which has escaped from the magnet mounting seat and cured at another area of the lens moving apparatus, may obstruct movement of other components constituting the lens moving apparatus, thus causing malfunction or breakage of the lens moving apparatus. A protruding portion, which has been formed differently from intended design due to the cured adhesive, may incur severe defections in the autofocusing function and handshake correction.
When an adhesive flows down and is cured during the procedure of attaching the magnet, the cured adhesive may be removed using tweezers, a knife or the like. However, there is another problem in that other contaminants may adhere to the lens moving apparatus during the removal procedure.
When contaminants infiltrate the lens moving apparatus constituting the camera module in the assembly of the camera module, the infiltrated contaminants may cause malfunction of the lens moving apparatus, quality degradation of captured images or the like. Furthermore, the lens moving apparatus and the camera module have to be firmly assembled.
For these reasons, a bonding operation of filling gaps between respective components with an adhesive may be performed in order to prevent contaminants from infiltrating the gaps while the respective components may be firmly coupled to each other using the adhesive.
The bonding operation has to solve the above problems and has to be rapidly and efficiently performed.